Norbert is unlike any other dog in the world. The tiny mixed pooch stands at only seven inches tall, but the impact he has had on other's lives is anything but small. Norbert is a therapy dog he was specifically trained to help people in hospitals, senior living centers, or wherever else a loving face might be needed.

Therapy dogs are not the same as service dogs, although they share some qualities. Service dogs prepare to help individuals with specific needs, such as people who are blind or physically disabled. Therapy dogs are trained to provide comfort to victims in various environments, and they're taught to deal with loud noises or unfamiliar terrain.

Three pound Norbert is one of the internet's most popular service dogs.

One of Norbert's favorite tricks is his high five, photos of which have been spread like a virus on social media. The dog has over 100k followers on Instagram, and currently has 175k followers on Facebook. In 2003, Norbert's owner Julie Freyermuth has used her dog's popularity to create a children's book focusing on Norbert's fictional adventures, titled ""

Recently, Norbert's popularity has spread to YouTube. In a video uploaded in August of 2015, Freyermuth feeds the small pup cheese in their Boston, MA home. In only a week's time, the video has accumulated over a million views. Commenters of the video were quick to point out that it appears that Norbert smiles near the end of the clip.